Bluetooth profiles and services are based on the Generic Attribute Profile (GATT). According to Bluetooth.org:
The profile describes a use case, roles and general behaviors based on the GATT functionality. Services are collections of characteristics and relationships to other services that encapsulate the behavior of part of a device. This also includes hierarchy of services, characteristics and attributes used in the attribute server. By following the guidance provided by the Bluetooth specification, developers can create applications to work with other Bluetooth devices.
What profiles and services are defined by the Bluetooth SIG, building on GATT?
Currently they range from an Alert Notification Profile (ANP) to a Tx Power Service (TPS). For example, the Proximity Profile (PXP) allows one device to detect whether another is within close range and, depending on an application, an alarm may be sounded at a particular threshold…
More to come about Bluetooth, and happy coding! 🙂